CARBIDE MASONRY DRILLS
1/8" to 1"

Fast Spiral Rotary: Generally used in rotary drilling. Speed range 450-700
RPM to 1/2" diameter, 350-500 RPM from 5/8" and up. Rotary bits do notbreak-up the concrete, but actually grind it away under pressure.

1/8" to 1"

Rotary/Percussion: Generally used in lightweight mechanical vibrating
hammers. Speed range 1300-3500 RPM at up to 50,000 blows per minute.
The impacting action created by the hammer fractures the concrete intotiny granules.
Rotary Hammer: Used in electro-pneumatic rotary hammers. Speed range
400-1000 RPM at up to 4500 blows per minute. SDS is currently most popular
shank type for holes to 5/8". Spline for holes 3/4" and larger.

5/32" to 1"
3/8" to 1-1/2"

1/8" to 1"

Rebar Cutter: Used to cut holes in embedded steel reinforcing bar. This is
the Rotary Hammer Drill's back-up.

7/8" to 4"

Core Bit: The most effective way of drilling a large hole since you are only
cutting the outside diameter. Both Rotary and Hammer types are available.
Rotary types require a great deal of pressure and are suitable for very brittleor thin materials. Hammer types offer speed and economy only if rebar isnot encountered.

NOMENCLATURE
A.N.S.I. B94-12-1977

OVERALL LENGTHAMERICAN NATIONAL STANDARDSINSTITUTE CARBIDE - TIPPEDDRILL TOLERANCES

Developed to insure maximum holding powerof concrete anchors by matching drill tolerances to anchor dimensions. Using a drill
which is worn or out of tolerance can drasticallyreduce an anchor's performance.
NOMINALNOMINALDRILLDRILLTOLERANCEDIAMETERDIAMETER
BAND

3/16"
1/4"
5/16"
3/8"7/16"
1/2"
9/16"

.206 - .198
.268 - .260
.335 - .327
.398 - .390
.468 - .458
.530 - .520
.592 - .582

5/8"
11/16"
3/4"
7/8"
1"
1-1/8"
1-1/4"TOLERANCEBANDDRILLING DEPTHNOT THE DRILLING DEPTH !

DRIVE

16 different types
depending upon therotary hammer used

SHANK

FLUTES

Does no drilling !

.660 - .650
.723 - .713
.787 - .775
.917 - .905
1.042 - 1.030
1.175 - 1.160
1.300 - 1.285

Drilling deeper than the flute length willcause binding and possible breakage

CARBIDE TIP is composed of a powder made up of Tungsten Carbide,Carbon, Cobalt and other metals which under heat and pressure areformed into a bit tip. Since there are only a few manufacturers of carbide,
it is the process and quality control of brazing the tip to the drill bodywhich determines the bits longevity and ultimate quality. The brazing
material, such as silver-copper alloy, must allow for the difference inexpansion and contraction between the carbide tip and the steel of thebody, as well as maintain shock-resistance.

HOW TO GET THE MOST LIFE OUT OF A BIT• The most important fact of all is REBAR KILLS! Rebar isthe number one enemy of a hammer bit.

• If the drill seems to slow down in its penetration rate, it
usually means that the carbide tip is getting dull. Continuing
to drill will reduce bit life. Carbide drills can be resharpened.

• When rebar is encountered STOP!

• Pouring water in the hole to keep dust down may cause
the carbide tip to shatter.

• Use a rotary rebar cutter which isdesigned to cut rebar• Do not drill deeper than the length of the flutes. Clogging
the flutes increases heat and torque and has accounted foralmost as many bit failures as rebar. Frequent withdrawal
from the hole will clean out the hole and lessen the chanceof the bit's binding.

• Continue with the hammer bit• Hammer drills are designed to do the work. Don't apply
too much pressure.

• Keep the shanks of hammer bits clean and well lubricated.
• A worn nose-piece can result in abnormal bit-shank wear.